Conventionally, a subject tracking technology originated in Patent Document 1 is considered to perform focus adjustment and a control of exposure conditions while keeping a user intended composition when a subject with relatively large motion (person, animal, vehicle, or the like) is photographed by a camera.
In the subject tracking technology, a main subject is tracked automatically, and the focus adjustment and the control of the exposure conditions are performed centering on the main subject.    Patent Document 1: Japanese Unexamined Patent Application Publication No. S60-263584